Technically it's a CRD (Cable Retention Device)
designed to utilize any existing port (USB, RJ11 or RJ45)
on a laptop computer as a stay or restraint to keep the very fragile AC power connector from being damaged from day to day tugging and pulling and jerking on the power cord.
Repairs to this connector as a result of the cumulative damage from day-to-day tugging and pulling can range from $100 to $250 or more if repairable.
The (Patent Pending) JerkStopper™ Cable Retention Device keeps you and others from causing costly damage to your Laptop Computer.
Call it insurance. . . .The AC power pin where your charging cable connects is very fragile and weak . If it gets damaged your laptop won't charge and the cost to repair it is huge! Some of the problems that you can have when this connector is damaged are noted on the right. The day-to-day tugging and pulling and jerking on the power cable causes these problems.
The JerkStopper™ is designed to minimize damage to this critical laptop component.